Bolster with absorption mechanism



Dec. 18, 1928.

P. R. DRENNING BOLSTER WITH ABSORPTION MECHANISM Filed Sept. 2, 1927 gl num 1 1oz recoil.

PatentedDecQlS, 1928. y

vlira-.Telis'rarlas' PATENT i OFFICE iv PERCY'R.' D RENNING, OF BALTIMORE, MARYLAND, AVSSIGNOR T0v T. H. SYMINGTON &

SON, INC., OF BALTIMORE, MARYLAND, CORPORATION OF MARYLAND.

BOLSTER WITH ABSORPTION MECHANISM. I

Application led September 2, 1927Lf'seria1 No. 217,173.

The invention relates to bolster const-ruction for railway car trucks and has special reference to absorption mechanism.

The principal object of the invention, gen- 5- erally stated, is to provide a railway car truck with a bolster embodying notr only ver- .1 tical but also lateral absorption means, both of which will operate and cooperate to counterbalance or neutralize any tendency of the 2o over curved'track, the structure thus accom-f plishing an automatic banking action which will offset any tendency of the carito develop side sway or roll as the result of the outward swing at a curve with thev consequent inward A more specilic object of the invention'is to provide aV bolster of this character having a combination of resilient and friction producing means constituting the absorption :su

downward thrust and therefore relieve the side frames and other truck parts of undue sti-ain resultingrom an excess load at either end of the bolster such as might result, for

' 3@ example, from passage of the wheels over a low spot in the rail.

' A further object of the invention vis tov provide a bolster structure of this character in whichthe combined springand friction' 40 producing means will operate to cushion not only the' downward thrusts above described.

but also the lateral motion ofthe bolster so that at no time will there occur any severe the truck parts.

to provide a bolster of this type unprovided with lateral motion rollers such as vare cmmonly used, the bolster supporting springs located within the side frames bein capable of sullicient rocking movement or istortion to accommodate the lateral motion of the bolster, the natural tendency of the springs to right themselves being sucient to return the parts to normal or straight track position mechanism which -will cushion a sudden trating the actionwhen lateral motion of the shocks such as mightcause injury to Vany ofy Still another object ofthe invention isafterthecessation of the forces causing the bolster to move laterally.

Still another object ot' `t-he'invention is to provide a bolster having these desirable characteristics and which may be installed as a replacement part within a truck of standard pattern' without involving any alterations or modilications in the structure thereof.

-An additional object is to provide a bolf ster of this type which will be comparatively simple and inexpensiveto manufacture, easy 'to install, positive in action, eiicient and durable in service, and a generalimprovement in the art.

To the attainment of the foregoing andl 70 other objects and advantages, the invention preferably consists in the details of construe-1 tion and the arrangement and coniblnation of parts to be hereinafter more fully de` scribed and claimed` and'illustrated in" th 75. accompanying drawing in which: Figure 1 is a plan view, partly broken away, of a truck bolster constructed in'accordance with my invention, the bolster wear columns of the side frames being shown in section, f

- Figure 2 is a vertical longitudinal section through the bolster constructed in accordance with my invention, and j Figure 34 is a diagrammatic view illuswindow openings Q defined between bolster wear columns 3, the windows being providedI for the reception of the end portions of whatever truck bolster forms part of the truck.y Within the lower portions of the window openings are provided suitable springs or nests of springs, indicated at 4, for supporting the loadimposed upon the bolster, these springs in turn being. suitably mounted upon a spring plank 5, illustrated only in Figure 3, which forms part of the regular equip-ment. f

The numeral 6 designates a portion ofv the car body bolster which is provided at its underside` Witha depending center plate 7 at opposite sides of which are depending bearing elements 8 for cooperation with king pin, not-shown, though it is conceivable whatever side bearings may be provided, if

any, on the truck bolster. Up to this point outer faces of the columns 3, the spacing be- A'ing determined by the contemplated extent of lateral motion of which the bolster may be capable in service. These lugs are of course intended to engage against the columns so as to limit the lateral motion. In-

wardly of the ends. the opposite sides of the bolster are formed or otherwise provided i with other stop lugs, 11 which are normally spaced inwardl an appreciable distance from the inner aces or confronting faces of the columns 3. It is preferablethat the arrangement of the lugs 10 and 11 be such that when the lugs 10 at one end are in engagement with the associated columns the lugs l1 at the opposite end will be in enga-gement with t-he other columns,lthe strain developed when these limiting stops come into play being thus distributed.

The bolster is here shown as having a relatively tall or deep central portion and as having a straight top wall i12 and a downwardly curved bot-tom wall 13, the straight to being probably immaterial but the curved Ibottoni being of importance inasmuch as it provides a truss 4structure which will possess great strength and rigidity. The end .portions 14 are preferably comparatively shallow and are formed with compartments 15 defined between the sides 16,'the outer ends 17 and transverse websor partitions 18 located a considerable distance inwardly from the ends, these compartments or pockets containing the absorption mechanism to be described.- At the center of the top 12 I have shown the bolster as provided with a center bearing 19 receiving the center plate 7 and the top and bottom wallsareboth shown as provided with sleevelike guides 20 adapted to receive the usual that such might be omitted if preferred. In the present instance the top is also represented, at least in Figure 2, as having bearing recesses or pockets 21 within which are received side bearing rollers 22` cooperating with the bearing elements 8 depending from the body bolster.

Located within the respective compartments 15 are upper and lower wedge mem- Vlatter being provided at their bottoms with plate or seat portions 25 resting upon the truck springs 4. The plate or seatportions 25 areof such width as to bev received within the window openings 2 and of suchflength as to project beyond the outer and inner faces v of tlie columns 3. At their inner ends, the plate or seat portions 25 are formed at one or more corners with lateral lugs 26 which overlap the columns 3 and which are normally 'in engagement therewith.v Clearly, outward movement of the members 24 is thus prevented. while inward movement, under conditions to be described, is possible.

The wedge members 23 and 24 may be of more or less block-like form and the foi'- iner are urged outwardly toward the bolster ends .17 by'-resilient means such as the coil springs designated by the numeral 27. In the present inst-ance the coacting wedge members.are represented as each having a plurality of inclined surfaces which/are in constant engagement. The surfaces on( the members 23 are designated by the numeral 28 while those on the members 24 are indicated at 29. The intermediate portions of these wedge members are of coursel cut away as at 30 and 31 to permit the necessary relative movement which occurs in service.

In the diagrammatic View, Figure 3, the

to the wedge members 23 and 24 are shown as each having a single inclined face or surface instead of two as above described. Fur- Awedge members 23a and 24 corresponding i ino wheels over a low spot in a rail, or a sudden undue pressure upon one of the side bearing rollers, such as would occur if the car body. sways or rocks toward one side, the wedge member 23 at said end may yield inwardly against the resistance of the spring or springs 27 against which it abuts, the wedgemember 24 thereupon moving upwardly with` respect to the wedge member 23, this movement, or relative movement of the wedge' members, producing friction at the coacting surfaces 28 and 29, the undue force exerted being absorbed by this friction so that the parts will be relieved ofthe strains and breakage thereof avoided. At the other end ofthe bolster, Where there is a corresponding decrease in the downward thrust, the spring or springs 27 will force or tend to force the wedge meinber 23 outwardly. When this happens the ian ' outwardly or whenever anything else occurs" inclined surfaces 28 riding upwardly along .the surfaces 29 will cau'sethe end of the bolster to be elevated so that upon the recoil, that is when the car body swings or rocks back, the swinging movement will be checked as the wedge member 23'will then be forced inwardly against the resistance of the spring or springs 27, friction 'occurring between the surfaces 28 and 29 and absorbing the shock.

1 IAvery important- 'feature ofthe inventionI is theac'tion that occurs upon lateral Vmotion vof the truck bolster. In regard to this feature vreference is had articularly to Figure 3 wherein the dot an dash line af-a .represents the normal vertical center line off the car. When the car passes over curved track so that centrifugal force tends' to throw it which tends to move t e car body laterally of the'track, it is apparent that inasmuch as'the center plate 7 fits closely within the center bearing 19 the truck bolster 14 will be moved Vin accordance with the movement of the car body, this movement being known as lateral'mot-ion. In view of the fact that the wedge members 24 are restrained against outward movement with respect to theside frames, owing to the engagement of the lugs 26 with the inner faces of the columns 3, it is apparent that when lateral motion of the 'truck bolster occursthe wedge member 23 at the 'outer end will move upwardly as the surfaces 28 thereon slide over the inclined sur- `faces 29 on thewedge member 24. As the wedge member 23 is in engagement always with the underside of the top wall of the bolsterithis outer end of the bolster will consequently b e elevated as clearly indicated in Figure 3." However, as the wedge memberl 23 at the inner end of the bolster (outer and inner as used herein mean withreference to the outer and inner rails of curved track) is free toimove inwardly or toward the vertical axis of the bolsters or the centerline of the car, it will do so inasmuch as the lateral motion of the bolster will reduce the spring press ure on'this wedge member 23 at the inner end of the bolster. v Furthermore, 'as the wedge Vmember 24 is always in engagement withthe end of the bolster, it will be carried .along by it, the resultbeing that the spring 4 at' the inner end of the bolster. will be distorted or slewed over 'at its upper end as clearly illustrated in Figure 3. When the lateral motion occursand the outer end of the bolster is elevatedwhile the inner end is lowered as above described, it is apparent that the vertical center line of the car will rotate about some ixed point and will assume the position indicated by the line {1 -b. There is thus a very clearly defined automatic banking action. Inasmuch as the spring 4 at the lowl or inner vend of the bolster is distorted `or slewed, it

has a natural tendency toright itself and will do so upon thecessatlon of the force tending claims hereunto appended.

to move theb'olster laterally, and this natural tendency of the spring will cause the parts to be restored to their normal' position they occupy when the car is travelling along `straighttrack. When reference is made to the spring 4 it should of course be understoodthat it is hardly likely that a single spring would be used, the practice being .to

employ several `arranged in a nestor group. L"

Asingle one is referred to only orconvenience in explanation. It mayv also bev remarked that no means has been disclosed for maintaining the spring or springs 27 and the spring 'or springsv 4 in position with respect to the elements engaged thereby'inasmuch as any mechanical means whatsoever may be employed for this purpose, various different expediente being commonly resorted toas is ywell known in the art.

From the foregoing description and a study of the drawing it' will 'be apparent that I have thus provided an absorption mechanism which will possess'unusul efficiency in that it takes care not` only of the excessive vertical thrusts' but also the horizontal thrusts vto which the parts are subjected under varying conditions of service. I have discovered that when a truck is equipped with a-bolster embodying the invention side ,sway or roll of a car is practically, if not entirely, eliminated,

'resulting -in a great increase in the life of the car body on vaccount of the avoiding of weaving -and a great decrease in the strain coming upon. all the truck parts. Furthermore, a bolster embodying the invention may be installed to replace one of the usual type without linvolving 'the employment of any other new parts. the construction, operation and advantages will be'readily apparent to one skilled in the art Without further explanation.

While I have shown and described the ypreferred embodiment' of the invention, it

should be understood that the disclosure is merely an exempliication of the principles involved as the right is reserved to make all such changes in the details otconstructionras will widen the field of utility and increase the.

adaptability yof the -device provided such changes constitute no departure from th spirit of the invention or the .scopey of the ion It is really believed that I center plate, a truck bolster having a center bearin o' closely receiving the center plate, said truck bolster being mounted for lateral mo` tion within a truck, supporting springs beneath the truck bolster, outwardly spring vpressed wedge members located within the truclr bolster, and wedge members engaged upon the truck springs and cooperating with said first named wedge members, said "second'named .wedge members being restrained against outward movement with respect to the truck.

3. In combination, a body bolster having a center plate, a truck bolster having a center bearing closely receiving the center plate, said truck bolster being mounted for lateral motion within a truck, supporting springs beneath the truclr bolster7 outwardly spring pressed wedge members located within the truck bolster, wedge members engaged upon the truck springs and cooperatinor with said first named wedge members, an means restraining the second named wedge members against outward movement with respect to the truck and permitting inward movement.

4. In combination with a body bolster having a center plate and depending bearing elements, a truck including side frames with window openings therein and having truck springs within the window openings,v

a truckbolster located within the window openings for lateral motion with "respect to the side frames, side bearings carried by the truck bolster 'and cooperating with said depending bearing elements, means limitinglat eral motion of the truck bolster in both disprings within the window openings, a truck bolsterlocated within the window openings for lateral motion with respect tothe sidel frames, side bearings carried bythe truck bolster and cooperating with lsaid )depending bearing elements, meanslimiting lateral motion of the truck bolster in both directions, outwardly urged wedge members within the end portions of the truck bolster, and means engaged upon the truck springs andcoacting with said wedge members, said means being restrained against movement in one direction with respect to the' adjacent side frames, said means comprising wedge members having stop elements thereon coacting with the inner faces of the side frames.

6. In combination with a body bolster, a

truck including side frames with truck springs, a truck bolster swivelly connected with the body bolster and mounted for lateral motion therewith with respect to the side frames, the truclr bolster being supported upon said truck springs, and wedge means coacting/-with the bolster and the side frames for banking the bolster upon. the occurrence of lateralimotion.

7. In combination with a body bolster, a truck including side frames with truclr` springs, a truck bolster swivelly connected with the body bolster and mounted for lateral motion therewith with respect to the side frames, the truck bolster being supported upon said truck springs, and Wedge means K coacting with the bolster and the side frames for banking the bolster upon the occurrence of lateral motion, said wedge means acting to cushion horizontal thrusts.

8. In combination with a body bolster, a truclr including side frames with truck springs, a truck bolster swivelly connected with the' body bolster and mounted for lateral motion therewith with respect to the side frames, the truck bolster being supported upon said truck springs, and wedge means coacting with the bolster and the side frames for 'banking the bolster upon the occurrence of lateral motion, said wedge means acting to cushion horizontal thrusts and coacting with the truck springs for cushioning vertical thrusts.

9. In the combination of a body bolster and truck including a bolster mounted yfor lateral motion with the body bolster and with respect to the truck side frames, the truck bolster being equipped with spring means and wedge means for cushioning vert-ical thrusts, means cooperating with the side frames andthe wedge means for raising `or lowering the ends of the truck bolster When lateral motion thereof occurs.

10. In the'combination of a body bolsterV and truck including a bolster mounted for lateral motion with the body bolster and with respect vto the truck sidevframes, the

truck bolster being Mequipped with spring .means and wedge means for cushioning vertical thrusts, means cooperating with the side frames and the wedge means for raising or lowering the ends of the truck bolster when ture.-

` .PERCY R. DRENNING.

In testimony` whereof I affix my signa-v 

